diff --git a/.gitea/workflows/ci.yaml b/.gitea/workflows/ci.yaml
new file mode 100644
index 0000000..6b95472
--- /dev/null
+++ b/.gitea/workflows/ci.yaml
@@ -0,0 +1,17 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - develop
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install jq
+        run: sudo apt-get update && sudo apt-get install -y jq
+      - name: Run shell tests
+        run: bash tests/entrypoint.sh
diff --git a/tests/entrypoint.sh b/tests/entrypoint.sh
new file mode 100644
index 0000000..e58a4df
--- /dev/null
+++ b/tests/entrypoint.sh
@@ -0,0 +1,117 @@
+#!/bin/bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d)"
+trap 'rm -rf "${TMP_DIR}"' EXIT
+
+assert_contains() {
+  local needle="$1"
+  local haystack="$2"
+
+  if ! grep -Fq "$needle" <<<"$haystack"; then
+    printf 'Expected output to contain: %s\n' "$needle" >&2
+    exit 1
+  fi
+}
+
+write_mock_curl() {
+  cat > "${TMP_DIR}/curl" <<'EOF'
+#!/bin/sh
+method=GET
+out_file=
+headers_file=
+url=
+while [ "$#" -gt 0 ]; do
+  case "$1" in
+    -X)
+      method=$2
+      shift 2
+      ;;
+    -D)
+      headers_file=$2
+      shift 2
+      ;;
+    -o)
+      out_file=$2
+      shift 2
+      ;;
+    -w)
+      shift 2
+      ;;
+    -H|-sS)
+      shift 1
+      ;;
+    *)
+      url=$1
+      shift
+      ;;
+  esac
+done
+
+status='HTTP/1.1 200 OK'
+code='200'
+body='[]'
+
+case "$url" in
+  *'/api/v1/packages/test-owner?type=nuget&page=1&limit=100')
+    body='[{"name":"pkg-a","version":"1.0.0","created_at":"2023-01-01T00:00:00Z"},{"name":"pkg-a","version":"1.1.0","created_at":"2023-02-01T00:00:00Z"},{"name":"pkg-b","version":"0.1.0","created_at":"2023-03-01T00:00:00Z"}]'
+    ;;
+  *'/api/v1/packages/test-owner/nuget/pkg-a/1.0.0')
+    if [ "$method" = "DELETE" ]; then
+      status='HTTP/1.1 204 No Content'
+      code='204'
+      body=''
+    fi
+    ;;
+esac
+
+printf '%s' "$body" > "$out_file"
+{
+  printf '%s\n' "$status"
+  printf 'X-Request-Id: req-123\n'
+} > "$headers_file"
+
+if [ "$method" = "DELETE" ] && [ -n "${MOCK_DELETE_FILE:-}" ]; then
+  printf '%s %s\n' "$method" "$url" >> "$MOCK_DELETE_FILE"
+fi
+
+printf '%s' "$code"
+EOF
+  chmod +x "${TMP_DIR}/curl"
+}
+
+run_entrypoint() {
+  PATH="${TMP_DIR}:$PATH" \
+    GITEA_SERVER_URL="https://gitea.example.com" \
+    GITEA_REPOSITORY="test-owner/test-repo" \
+    env "$@" "${ROOT_DIR}/entrypoint.sh" 2>&1
+}
+
+write_mock_curl
+
+output="$(run_entrypoint INPUT_RUNNER_TOKEN=abc INPUT_KEEP_VERSIONS=1 INPUT_DRY_RUN=true)"
+assert_contains "Using token from inputs.RUNNER_TOKEN" "$output"
+assert_contains "keep_versions=1" "$output"
+assert_contains "dry_run=true" "$output"
+assert_contains "request_id=req-123" "$output"
+assert_contains "[DRY-RUN] Would delete package pkg-a version 1.0.0" "$output"
+
+output="$(run_entrypoint GITEA_TOKEN=secret INPUT_KEEP_VERSIONS=1 INPUT_DRY_RUN=true)"
+assert_contains "Using token from secrets.GITEA_TOKEN" "$output"
+
+if run_entrypoint INPUT_KEEP_VERSIONS=-1 >/dev/null 2>&1; then
+  printf 'Expected invalid keep_versions to fail\n' >&2
+  exit 1
+fi
+
+if run_entrypoint >/dev/null 2>&1; then
+  printf 'Expected missing token to fail\n' >&2
+  exit 1
+fi
+
+delete_log="${TMP_DIR}/delete.log"
+output="$(MOCK_DELETE_FILE="$delete_log" run_entrypoint INPUT_RUNNER_TOKEN=abc INPUT_KEEP_VERSIONS=1 INPUT_DRY_RUN=false)"
+assert_contains "Deleted package pkg-a version 1.0.0 -> 204 No Content" "$output"
+assert_contains "Summary: packages=2 versions=3 kept=2 candidates=1 deleted=1 skipped=0 errors=0 dry_run=false" "$output"
+assert_contains "DELETE https://gitea.example.com/api/v1/packages/test-owner/nuget/pkg-a/1.0.0" "$(cat "$delete_log")"